Nanotubes (such as those formed from carbon1 and boron-nitride2) are versatile nanoscale building blocks which have already been incorporated into a variety of useful devices. Although nanotubes are relatively easy to synthesize, at present it is difficult to control at the synthesis level the geometrical configurations, including length, number of walls, chirality, etc. Of great utility would be a method whereby the geometrical features of nanotubes could be shape altered post-synthesis, either before or after their incorporation into functional nanodevices.
A versatile method for cutting nanotubes would be particularly useful. Nanotube devices are often made by poorly controlled solution deposition or chemical growth techniques, which can easily lead to device components contacting multiple nanotubes where only one is desired. A method for removing excess nanotubes is therefore required. Other applications, such as carbon nanotube tipped atomic force microscopy (AFM) cantilevers3, require that nanotubes be cut down to a certain length for optimum device performance. It may additionally be preferred that AFM tips be “sharpened” to provide even higher capabilities. Finally, certain nanotube-based systems, such as nanoscale rotational bearings, require nanotubes that have been selectively modified4,5.